1. Field
The present disclosure relates to complementary metal oxide semiconductor (CMOS) devices and/or methods of manufacturing the same, and more particularly, to CMOS devices including both an n-type transistor layer and a p-type transistor layer on a silicon substrate and/or methods of manufacturing the same.
2. Description of the Related Art
Extensive research has been conducted to develop devices that use compound semiconductors, for example, Group III-V semiconductor materials. Since the electron mobility of Group III-V compound semiconductor materials is higher by about 10 times to about 103 times than the electron mobility of silicon (Si), the Group III-V compound semiconductor materials are used for high-speed channels in complementary metal oxide semiconductor (CMOS) devices or are suitably applied to high-efficiency Group III-V solar cells.
Group III-V substrates formed of materials, such as InP, GaAs, GaSb, and InSb, have been widely used as substrates for growing Group III-V semiconductor materials. However, the Group III-V substrates are more expensive and more likely to be damaged during a process than Si substrates. Also, the maximum size of commercial substrates is about 6 inches, and the Group III-V substrates are difficult to manufacture in large sizes. In order to overcome these problems, semiconductor devices using Si substrates instead of Group III-V substrates have been developed.
Recently, interest in the technology for implementing silicon-based photonics integrated circuits has increased. In line with this trend, demand for the technology using Group III-V compound semiconductor materials to form light sources, such as light emitting diodes (LEDs) and laser diodes (LDs), and transistors for high-speed devices on Si substrates has increased. When a Group III-V compound semiconductor is integrated on a large-sized Si substrate, the known silicon manufacturing processes may be used without modification, and the costs thereof may be greatly reduced.
However, various defects are generated due to the lattice constant difference and the thermal expansion coefficient difference between a Group III-V compound semiconductor material and an Si substrate, and the application of a compound Group III-V semiconductor material to devices is restricted due to these defects. For example, when a semiconductor thin film having a smaller lattice constant than a substrate is grown, a dislocation may occur due to a compressive stress; and when a semiconductor thin film having a larger lattice constant than a substrate is grown, a crack may be generated due to a tensile stress.